Creating paths in AI

Hey guys, I am a sophomore ID student at VT. I was wondering if anyone could post a detailed tutorial on how to create good paths on either AI or PS. I am only familiar with creating paths on PS, but I am willing to learn on either. I really liked the line work done in the Illustrator to Photoshop rendo tutorial. That is what I am looking for.

Thanks guys

Skinny has done some good ones for this